What is a linked list?

A linked list is a data structure used to store a collection of elements in a linear order. Unlike arrays, linked lists do not require contiguous memory allocation, allowing for dynamic memory usage. Here are the key characteristics and components:

Key Characteristics:

1. Nodes: A linked list is made up of nodes, where each node contains:

   • Data: The value or information stored in the node.
   • Pointer/Reference: A link to the next node in the sequence.

2. Dynamic Size: Linked lists can grow or shrink in size as needed, making them more flexible than arrays.

3. Non-contiguous Memory: Nodes can be scattered throughout memory, as each node points to the next one.

Types of Linked Lists:

1. Singly Linked List: Each node points to the next node, and traversal is one-way.

   • Example structure:

     struct Node {
         int data;
         struct Node* next;
     };

2. Doubly Linked List: Each node points to both the next and the previous node, allowing for two-way traversal.

   • Example structure:

     struct Node {
         int data;
         struct Node* next;
         struct Node* prev;
     };

3. Circular Linked List: The last node points back to the first node, forming a circle. This can be singly or doubly linked.

Basic Operations:

• Insertion: Adding a new node at the beginning, end, or a specific position.
• Deletion: Removing a node from the list.
• Traversal: Accessing each node to read or modify data.

Example in C (Singly Linked List):

#include <stdio.h>
#include <stdlib.h>

struct Node {
    int data;
    struct Node* next;
};

void insert(struct Node** head, int new_data) {
    struct Node* new_node = (struct Node*)malloc(sizeof(struct Node));
    new_node->data = new_data;
    new_node->next = (*head);
    (*head) = new_node;
}

void printList(struct Node* node) {
    while (node != NULL) {
        printf("%d -> ", node->data);
        node = node->next;
    }
    printf("NULL\n");
}

Further Learning:

To explore linked lists in depth, consider:

• LabEx Labs: Look for labs focused on data structures and linked lists.
• Online Tutorials: Websites like GeeksforGeeks or educational platforms that cover data structures.

Feel free to ask if you have more questions or need further clarification!